[Asus  Eee Pad Transformer Prime] rogerzoul:
Something as simple as moving your hand in front of a screen can change the RF environment around the tablet and the antennas. If you have a weak lock to start with, you can lose it and possibly not be able to regain it. Software may play some role, but the best situation possible is to locate and orient the antennas for optimal reception.

---------- Post added at 10:11 PM ---------- Previous post was at 09:30 PM ----------

I have an iPad 2 Wifi and an Acer Iconia Tab A500.

I'm a big fan of using tablets for GPS-based navigation in my car. I also use my tablets to listen to music and audio books and I'll run the nav (Navigon) even when I'm going back & forth to/from work...just because...but music or audio book will be playing playing through my car's music system.

With the iPad 2, I use a Dual XGPS 150 gps receiver and a blue-tooth link to the iPad. This works extremely well...I'd venture to say it works better than it would were a GPS antenna inside the iPad...the Dual is on the dash and has clear view of the sky...the iPad is mounted in a holder inside the cabin and thus is partially blocked from the sky. Navigon works great on the iPad with music or audio playing in the background. When Navigon gives spoken directions, it lowers the volume of the music or audio so you can those directions and this makes for a very nice experience.

Now, the Acer Iconia has a built-in aGPS. This tablet also has a metal back though it appears there are strips of plastic on either ends. I'm not sure where the gps antenna is located. Still, this tablet will not get lock inside and it can take 10 to 15 minutes to get lock when I'm in my driveway with the sky above. I use Navigon on it as well..and I have actually used this for navigation to some places I have not gone before. I've seen this tablet lose GPS lock at seemingly random times while driving, even if there is open sky above. Not easy to explain. And don't let there by clouds or rain about..it will quickly lose lock. Get under some trees and lock is gone. Start a trip under trees and you have to wait until you get a clear view of the sky before getting lock. I mount this tablet in the same holder as I mount the iPad 2 (the Arkon holder will hold most tablets).

When HC 3.2.1 was released for this tablet by Acer, some changes were made so that the Dual XGPS works with the Acer. Prior versions were supposed to work, but didn't. So, I can now use the receiver with the Acer and when I do nav I don't lose lock anymore. However, Navigon for Android is not as nicely implemented as it is for iOS. It doesn't look as nice...the maps don't look as nice as they do on the iPad because the screen is so wide compared to its height. But the real killer is that music and audio coming out of the Acer to my car's music system sounds like crap. Total crap that's so bad I can hardly stand to listen to it. This is in comparison to how the system sounds when used with iPad 2...I'm using my own ripped music on both systems and the difference is night and day. Also, when Navigon gives spoken directions, the directions are at the same volume as the music, so the overall experience is not nearly as seamless. It's kinda sad. I think some of the blame here may lie with Navigon for Android, but it is not clearly evident to me. But the GPS receiver works with HC 3.2.1 and I'm hoping it will also work with ICS.

I have a T201 on the way...i'm hoping to replace the Acer with this Android tablet (I'm keeping my iPad 2, as it just kicks ass when it comes to tablet-based apps and I actually use it for work, not just entertainment). I was hoping the Prime would have good GPS as I've been told that the T101 had really good GPS (note: I got the Acer because I could not find the OG Transformer anywhere). So it seems the GPS will suck just like the one in the Acer...but since I have the Dual I can deal with this -- provide the bluetooth works as it should. I'm just hoping that music / audio out of the 3.5mm headphone jack doesn't sound like crap...I'm not sure if I can expect anything different from Navigon for Android however.

It seems to me that a tablet's design ought to consider what antennas are included with the hardware. Antenna orientation and location must be factored into the tablet's design and constraints need to be placed on the housing of the tablet to accommodate the on-board antennas. It seems that Apple left out the GPS antenna on the Wifi iPad and it shows clearly in the housing....when the GPS/cellular antennas are included, the housing is changed to account for those antennas. Apparently, similar things have been done by some Android tablet makers and not by others. That's how it goes when you have lots and lots of vendors producing tablets...and then you have testing websites that don't fully test all the functionality of the tablets (why would anyone use a tablet for GPS -- that seems like a stupid question to me when you see how nice a map looks on a large screen). I wonder how many tablets have crap sound coming from the 3.5mm headphone jack? Do they test this or do they assume again that no one is going to listen to audio/music on a tablet?

I will deal with the crap GPS in the Prime, but I won't deal with crap sound coming from the headphone jack when playing the same mp3 as I have on my iPad.